Field of the Invention
The present invention relates to a vibration type driving device. More particularly, the present invention relates to a vibration type driving device that causes relative rotation of a driven body by combining vibrations in different vibration modes.
Description of the Related Art
There has been proposed a vibration type driving device for generating rotary driving with a vibrator that combines vibrations in different vibration modes (shapes). U.S. Patent Application Publication No. 2005/242686 A1 discloses that relative rotary movement is generated in a substantially disk-shaped driven body while a rectangular flat vibrator is pressed against a bottom surface of the driven body. FIG. 12 schematically illustrates principal components of a vibration type driving device of this type. A driven body 5 is held rotatably on a center axis thereof. While the driven body 5 is spaced from a vibrator 1 in FIG. 12, in actuality, the driven body 5 is in pressing contact with upper faces of projections 2-1 and 2-2 of the vibrator 1. The vibrator 1 generates driving force in the X-axis direction of FIG. 12, and is located to rotate the driven body 5 in the tangential direction.